This invention relates to heating and dispensing, or alternatively, cooling and dispensing, food, beverages and other materials, and more particularly to devices and methods for self-contained heating and dispensing, or alternatively, cooling and dispensing, of food, beverages and other materials.
Portable heating and cooling devices are known. Compact, self-heating devices that produce heat through exothermic chemical reactions are known. For example, U.S. Pat. No. 4,397,315 discloses a device having an outer envelope and an inner envelope, with the outer envelope containing sodium thiosulfate, and the inner envelope containing ethylene glycol. The walls of the inner envelope are rupturable, allowing the contents of each envelope to mix. U.S. Pat. No. 5,035,230 discloses a heat pack having two compartments separated by a frangible seal. Potassium permanganate oxidizing agent coated with sodium silicate is provided in one zone of the heat pack, and aqueous ethylene glycol fuel is provided in the other zone. In operation of the device, a seal between the two zones is compromised to allow the reactants to come in contact with each other. U.S. Pat. No. 6,116,231 discloses another heat pack having two compartments separated by a frangible seal, in which gelling agent is employed to assist in the regulation of heat evolution in the heat pack. U.S. Pat. No. 5,984,953 discloses another heat pack having two compartments in which a stifffenable gel is employed, along with the evaporation and reversible removal of solvent from the gel to assist in the regulation of heat evolution in the heat pack.
Devices for producing heat or cold by heat of dilution rather than by chemical reaction are also known. U.S. Pat. No. 3,804,077 describes a heat pack which contains a water soluble chemical (e.g., calcium chloride) and a starch material acting as a gelling agent in one zone, and water in another zone.
Devices for producing cold by mixing of materials are also known. U.S. Pat. No. 6,099,555, for example, describes a cold pack having two compartments separated by a frangible seal, in which gelling agent is employed to assist in the regulation of cold evolution in the cold pack.
However, transfer of hot or cold food or beverage from any of these prior art heating or cooling devices to an unheated vessel can result in rapid cooling (or warming) of the food or beverage. The food or beverage could be undesirably cool (or warm) within a short period of time.
The invention involves a single-use, disposable heater that can heat a quantity of material to a desired temperature. Alternatively, the invention relates to a cooling device that can cool a quantity of material to a desired temperature. Either device can also serve as a container from which to dispense or further utilize the container""s contents.
In one aspect, the invention provides a self-contained device for heating material and dispensing the heated material. The device includes at least one activatable heat-generating element, and at least one container for containing material to be heated by the heat-generating element. The container is in thermal contact with the heat-generating element, and the container includes an openable seal, which can be a repeatably openable seal. The material to be heated can be contained within the device prior to activation of the heat-generating element. The container can be made of, for example, polyethylene, polypropylene, polyester, metal foil, metallized plastic film, rubber, vinyl, or vinyl-coated fabric. The heat-generating element can include a heat pack providing heat through an exothermic chemical reaction, such as a reduction-oxidation reaction. The heat pack can include an oxidizing agent, a fuel, and a solvent, with the oxidizing agent and fuel separated by a frangible seal. The heat pack can also include a gelling agent, which can, for example, form a gel upon activation of the heat pack. The heat pack can also include a phase-change material. The heat pack itself can include an envelope made of, for example, polyethylene, polypropylene, polyester, metal foil, metallized plastic film, rubber, vinyl, or vinyl-coated fabric. The device can be made able to stand upright, for example by the use of gussets.
In another aspect, the invention provides a method for heating material. The method includes the steps of activating a heat-generating element of the device described above, filling the container with a material to be heated, and allowing the material to be heated to a desired temperature. The step of filling can be performed prior to the step of activating.
In yet a further aspect, the invention provides a self-contained device for cooling material and dispensing heated material. The device includes at least one activatable cold-generating element, and at least one container for containing material to be cooled by said cold-generating element. The container is in thermal contact with the cold-generating element, and the container includes an openable seal. The cold-generating element can include a cold pack providing cold through a dilution reaction. The cold pack can also include a gelling agent. The device can be made able to stand upright, for example, by using gussets.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.
Other features and advantages of the invention will be apparent from the following detailed description, and from the claims.